US8968040B2 - Method of operating a marine vessel propulsion system, marine vessel propulsion system, and marine vessel including the same - Google Patents

Method of operating a marine vessel propulsion system, marine vessel propulsion system, and marine vessel including the same Download PDF

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US8968040B2
US8968040B2 US14/048,262 US201314048262A US8968040B2 US 8968040 B2 US8968040 B2 US 8968040B2 US 201314048262 A US201314048262 A US 201314048262A US 8968040 B2 US8968040 B2 US 8968040B2
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Prior art keywords
malfunction
turning angle
outboard motors
turning
outboard
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US20140106631A1 (en
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Makoto Ito
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Yamaha Motor Co Ltd
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Yamaha Motor Co Ltd
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Assigned to YAMAHA HATSUDOKI KABUSHIKI KAISHA reassignment YAMAHA HATSUDOKI KABUSHIKI KAISHA ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: ITO, MAKOTO
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H21/00—Use of propulsion power plant or units on vessels
    • B63H21/21—Control means for engine or transmission, specially adapted for use on marine vessels
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H20/00—Outboard propulsion units, e.g. outboard motors or Z-drives; Arrangements thereof on vessels
    • B63H20/08—Means enabling movement of the position of the propulsion element, e.g. for trim, tilt or steering; Control of trim or tilt
    • B63H20/12—Means enabling steering
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H25/00—Steering; Slowing-down otherwise than by use of propulsive elements; Dynamic anchoring, i.e. positioning vessels by means of main or auxiliary propulsive elements
    • B63H25/42—Steering or dynamic anchoring by propulsive elements; Steering or dynamic anchoring by propellers used therefor only; Steering or dynamic anchoring by rudders carrying propellers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H20/00—Outboard propulsion units, e.g. outboard motors or Z-drives; Arrangements thereof on vessels
    • B63H2020/003—Arrangements of two, or more outboard propulsion units

Definitions

  • the present invention relates to a method of operating a marine vessel propulsion system that includes an outboard motor.
  • the present invention also relates to a marine vessel propulsion system with an outboard motor and a marine vessel including the same.
  • An outboard motor is an example of a propulsion device for a marine vessel and includes a motor and a propeller driven by the motor.
  • the outboard motor is attached to a stern of the marine vessel in a state enabling turning in right and left directions.
  • the marine vessel is equipped with a steering apparatus to control a turning angle of the outboard motor.
  • the steering apparatus turns the outboard motor in accordance with the operation of a steering handle by a marine vessel operator. In a case of a multiple installation arrangement in which a plurality of outboard motors are installed at the stern, the steering apparatus turns the plurality of outboard motors in synchronization.
  • U.S. 2010/0151750 A1 discloses an arrangement where a steering angle of a steering handle is detected by a steering angle sensor and a plurality of outboard motors are turned in accordance with the detection result.
  • the turning angle control of the corresponding outboard motor is stopped.
  • a turning angle range of another normally functioning outboard motor is then restricted in accordance with the turning angle of the outboard motor with the turning angle control malfunction.
  • the turning angle control of the normally functioning outboard motor is performed within the restricted turning angle range. Turning performance of the marine vessel can thus be secured while avoiding interference of the normally functioning outboard motor with the outboard motor with the turning angle control malfunction.
  • Preferred embodiments of the present invention provide a method of operating a marine vessel propulsion system, a marine vessel propulsion system, and a marine vessel including the same by which a turning performance of a marine vessel is secured by simple control when there is a malfunction in the turning angle control of at least one of a plurality of outboard motors.
  • a first preferred embodiment of the present invention provides a method of operating a marine vessel propulsion system that includes a plurality of outboard motors, each including a motor and a propeller rotated by the motor, and a steering apparatus arranged to control turning angles of the plurality of the outboard motors and where the steering apparatus includes a steering member and a plurality of turning mechanisms arranged to turn each of the plurality of outboard motors individually in accordance with an operation of the steering member and each of the turning mechanisms includes a hydraulic cylinder including two cylinder chambers partitioned by a piston and a normally-closed bypass valve to put the two cylinder chambers of the hydraulic cylinder in communication with each other, the method of operating the marine vessel propulsion system including a step of judging whether or not there is a malfunction in a turning angle control of at least one of the outboard motors, a step where, when it is judged that there is the malfunction in the turning angle control of the at least one
  • the bypass valve of the turning mechanism corresponding to the at least one of the outboard motors with the turning angle control malfunction (hereinafter referred to as the “malfunctioning outboard motor”), is put in the open state.
  • the malfunctioning outboard motor is thus put in a state where, although the turning angle control thereof cannot be performed, it can be turned freely in the right and left directions. Also, the power transmission between the motor and the propeller of the malfunctioning outboard motor is kept in the interrupted state. Generation of a propulsive force by the malfunctioning outboard motor is thus stopped.
  • the power transmission between the motor and the propeller is allowed in the other outboard motor or motors (a normally functioning outboard motor without a turning angle control malfunction).
  • a propulsive force can thus be generated by the normally functioning outboard motor.
  • the turning angle control of the normally functioning outboard motor is performed as is done normally and thus the turning performance of the marine vessel is secured by the turning angle control of the normally functioning outboard motor.
  • the marine vessel operator can steer the marine vessel by operating the steering member.
  • the malfunctioning outboard motor is put in a state where the generation of a propulsive force is stopped but turning in the right and left directions is performed freely.
  • the malfunctioning outboard motor is turned by being pushed by the normally functioning outboard motor.
  • the malfunctioning outboard motor is turned in the same direction as the other normally functioning outboard motor in accordance with a water stream that forms at a periphery of the malfunctioning outboard motor. A possibility of the normally functioning outboard motor contacting the malfunctioning outboard motor during the turning angle control of the normally functioning outboard motor is thus low, and even when contact of the malfunctioning outboard motor with the normally functioning outboard motor occurs, a load due to the contact is small.
  • the method of operating a marine vessel propulsion system may further include a step where, when it is judged that there is a malfunction in the turning angle control of at least one of the outboard motors, a marine vessel operator is urged to open the bypass valve of the turning mechanism corresponding to the at least one of the outboard motors judged to have the malfunction in the turning angle control.
  • the bypass valve of the turning mechanism corresponding to the malfunctioning outboard motor can be opened reliably by the marine vessel operator.
  • the method of operating a marine vessel propulsion system may further include a step of judging whether there is the malfunction in the turning angle control of all of the outboard motors or a there is the malfunction in the turning angle control of the at least one of the outboard motors, and a step where, when it is judged that there is the malfunction in the turning angle control of the at least one of the outboard motors, a marine vessel operator is urged to open the bypass valve of the turning mechanism corresponding to the at least one of the outboard motors judged to have a malfunction in the turning angle control.
  • the bypass valve of the turning mechanism corresponding to the malfunctioning outboard motor can be opened reliably by the marine vessel operator.
  • the method of operating a marine vessel propulsion system may further include a step where, when it is judged that there is the malfunction in the turning angle control of all of the outboard motors, the marine vessel operator is notified that there is the malfunction in the turning angle control of all of the outboard motors.
  • the method of operating a marine vessel propulsion system may further include a step where, when it is judged that there is the malfunction in the turning angle control of all of the outboard motors, all of the outboard motors are moved to respective turning angle midpoints thereof and not less than one of the plurality of outboard motors is made to generate a propulsive force in the state where all of the outboard motors are fixed at the respective turning angle midpoints.
  • the marine vessel when there is the malfunction in the turning angle control of all of the outboard motors, the marine vessel can be made to turn by making use of an output difference among the plurality of outboard motors in the state where all of the outboard motors are fixed at the respective turning angle midpoints. Thus, even when there is the malfunction in the turning angle control of all of the outboard motors, the turning performance of the marine vessel is secured.
  • the method of operating a marine vessel propulsion system may further include a step where, when it is judged that there is the malfunction in the turning angle control of all of the outboard motors, the bypass valves of the turning mechanisms corresponding to all of the outboard motors are opened, all of the outboard motors are moved to the respective turning angle midpoints, and the bypass valves of the turning mechanisms corresponding to all of the outboard motors are thereafter closed.
  • the method of operating a marine vessel propulsion system may further include a step where, when it is judged that there is the malfunction in the turning angle control of all of the outboard motors, a rotational speed of the motor is restricted to no more than a predetermined value in all of the outboard motors.
  • the marine vessel can be turned by making use of the propulsive force of the outboard motors without performing turning angle control of the outboard motors.
  • the propulsive force of the outboard motors is too great, it may be difficult to obtain a turning behavior that is intended by the marine vessel operator.
  • the rotational speed of the motor is restricted to no more than the predetermined value in all of the outboard motors when there is the malfunction in the turning angle control of all of the outboard motors. The propulsive force of the outboard motors are thus prevented from becoming too large and marine vessel maneuvering is made easy.
  • the power control step may include a step of restricting the rotational speed of the motor in the other outboard motor or motors to no more than a predetermined value.
  • the turning angle control of another normally functioning outboard motor is performed, wherein the normally functioning outboard motor may contact the malfunctioning outboard motor.
  • the rotational speed of the motor is restricted to no more than the predetermined value in the other normally functioning outboard motor or motors. A load due to the contact of the normally functioning outboard motor with the malfunctioning outboard motor is thus significantly reduced or prevented.
  • the method of operating a marine vessel propulsion system may further include a step where, when it is judged that there is the malfunction in the turning angle control of the at least one of the outboard motors, the marine vessel is made to run at a vessel speed lower than a vessel speed corresponding to a maximum propulsive force that can be generated by all of the outboard motors.
  • the marine vessel runs at the vessel speed lower than the vessel speed corresponding to the maximum propulsive force that can be generated by all of the outboard motors and thus even when a normally functioning outboard motor contacts the malfunctioning outboard motor, the load due to the contact is significantly reduced.
  • a second preferred embodiment of the present invention provides a marine vessel propulsion system including a plurality of outboard motors, each including a motor and a propeller rotated by the motor, and a steering apparatus arranged to control turning angles of the plurality of the outboard motors and where the steering apparatus includes a steering member and a plurality of turning mechanisms to turn each of the plurality of outboard motors individually in accordance with an operation of the steering member, and each of the turning mechanisms includes a hydraulic cylinder including two cylinder chambers partitioned by a piston and a normally-closed bypass valve to put the two cylinder chambers of the hydraulic cylinder in communication with each other, the marine vessel propulsion system further including a malfunction judging unit arranged to judge whether or not there is the malfunction in the turning angle control of at least one of the outboard motors, a notifying unit that, when the malfunction judging unit judges that there is the malfunction in the turning angle control of the at least one of the outboard motors, urges the marine vessel operator to open the bypass valve of the turning mechanism corresponding to
  • the marine vessel operator when there is the malfunction in the turning angle control of the at least one of the outboard motors, the marine vessel operator is urged to open the bypass valve of the turning mechanism corresponding to the at least one of the outboard motors with the turning angle control malfunction (hereinafter referred to as the “malfunctioning outboard motor”).
  • the malfunctioning outboard motor When the marine vessel operator opens the bypass valve of the turning mechanism corresponding to the malfunctioning outboard motor, the malfunctioning outboard motor is put in a state where, although the turning angle control thereof cannot be performed, it can be turned freely in the right and left directions. Also, the power transmission between the motor and the propeller of the malfunctioning outboard motor is kept in the interrupted state. Generation of a propulsive force by the malfunctioning outboard motor is thus stopped.
  • the power transmission between the motor and the propeller is allowed in the other outboard motor or motors (a normally functioning outboard motor without a turning angle control malfunction).
  • a propulsive force can thus be generated by the normally functioning outboard motor.
  • the turning angle control of the normally functioning outboard motor is performed as is done normally and thus the turning performance of the marine vessel is secured by the turning angle control of the normally functioning outboard motor.
  • the marine vessel operator can steer the marine vessel by operating the steering member.
  • the malfunctioning outboard motor is put in a state where the generation of a propulsive force is stopped but turning in the right and left directions can be performed freely.
  • the malfunctioning outboard motor is turned in the same direction as the other normally functioning outboard motor in accordance with a water stream at a periphery of the marine vessel.
  • a possibility of the normally functioning outboard motor contacting the malfunctioning outboard motor during the turning angle control of the normally functioning outboard motor is thus low. Also, even when the normally functioning outboard motor contacts the malfunctioning outboard motor, a load due to the contact is small.
  • the marine vessel propulsion system may further include a restricting unit that, when the malfunction judging unit judges that there is the malfunction in the turning angle control of the at least one of the outboard motors, restricts a rotational speed of the motor to no more than a predetermined value in the at least one of the outboard motors judged to have a malfunction in the turning angle control.
  • Each of the bypass valves may be a manually opened/closed bypass valve.
  • Each of the bypass valves may be an automatically opened/closed type bypass valve.
  • the marine vessel propulsion system may further include a turning angle control stopping unit that, when the malfunction judging unit judges that there is the malfunction in the turning angle control of all of the outboard motors, stops the turning angle control of all of the outboard motors.
  • a turning angle control stopping unit that, when the malfunction judging unit judges that there is the malfunction in the turning angle control of all of the outboard motors, stops the turning angle control of all of the outboard motors.
  • the malfunction judging unit may be arranged to judge that there is the malfunction in the turning angle control of all of the outboard motors when a malfunction due to an input system in common to all of the turning mechanisms is detected and to judge that there is the malfunction in the turning angle control of the at least one of the outboard motors when a malfunction due to output systems of the respective turning mechanisms is detected.
  • the malfunction due to the input system may include a malfunction of an operation amount detection sensor arranged to detect an operation amount of the steering member.
  • the malfunction due to the output systems includes a malfunction of turning angle sensors arranged to detect the turning angles of the outboard motors and a malfunction of the respective turning mechanisms.
  • a third preferred embodiment of the present invention provides a marine vessel including a hull and a marine vessel propulsion system attached to the hull.
  • the marine vessel operator can open the bypass valve of the turning mechanism corresponding to the malfunctioning outboard motor. Also, the power transmission between the motor and the propeller of the malfunctioning outboard motor is kept in the interrupted state. On the other hand, the power transmission between the motor and the propeller in the other normally functioning outboard motor or motors is allowed. Also, the turning angle control of the normally functioning outboard motor is performed as is done normally and thus the turning performance of the marine vessel is secured by the turning angle control of the normally functioning outboard motor. Thus, even when there is the malfunction in the turning angle control of the at least one of the outboard motors, the marine vessel operator can steer the marine vessel by operating the steering member.
  • FIG. 1 is a perspective view for describing an arrangement of a marine vessel according to a preferred embodiment of the present invention.
  • FIG. 2 is a schematic side view of an arrangement example of an outboard motor.
  • FIG. 3 is an arrangement diagram for describing an arrangement of a turning mechanism.
  • FIG. 4 is a block diagram for describing an electrical arrangement of a principal portion of the marine vessel.
  • FIGS. 5A to 5F are schematic views for describing relationships of respective lever positions to adjust a propulsive force of the marine vessel and movements of a hull.
  • FIG. 6 is a flowchart of procedures of a basic target turning angle computing process performed by a main ECU and procedures of a motor control process performed by a turning ECU.
  • FIG. 7A is a flowchart of a portion of procedures of a malfunction operation control process executed by the main ECU.
  • FIG. 7B is a flowchart of a portion of the procedures of the malfunction operation control process executed by the main ECU.
  • FIG. 7C is a flowchart of a portion of the procedures of the malfunction operation control process executed by the main ECU.
  • FIG. 8 is a schematic view of an example of an operation guidance screen displayed on a display in step S 24 of FIG. 7A .
  • FIG. 9 is a schematic view of an example of an operation guidance screen displayed on the display in step S 29 of FIG. 7A .
  • FIG. 10 is a schematic view of an example of an operation guidance screen displayed on the display in step S 35 of FIG. 7C .
  • FIGS. 11A to 11C are schematic views for specifically describing a process of steps S 21 to S 25 of FIG. 7A .
  • FIG. 1 is a perspective view for describing an arrangement of a marine vessel according to a preferred embodiment of the present invention.
  • the marine vessel 1 includes a hull 2 , a plurality of outboard motors 3 as marine vessel propulsion devices, and a steering apparatus 4 that controls turning angles of the respective outboard motors 3 .
  • Three outboard motors 3 are provided in the present preferred embodiment.
  • the outboard motors 3 are aligned and attached along a stern of the hull 2 and are put in states enabling swinging (turning) in the right and left directions.
  • the outboard motor disposed at a starboard side shall be referred to as the “starboard outboard motor 3 S,” the outboard motor disposed at a center shall be referred to as the “central outboard motor 3 C,” and the outboard motor disposed at a port side shall be referred to as the “port outboard motor 3 P.”
  • Each of the outboard motors 3 includes an engine (internal combustion engine as an example of a motor) and a propeller (screw) and generates a propulsive force by rotation of the propeller by a driving force of the engine.
  • a marine vessel operator compartment 5 is provided at a front portion (stem portion) of the hull 2 .
  • the marine vessel operator compartment 5 includes a steering handle 6 as a steering member, a remote controller 7 , an operation panel 8 , a display 9 , and a main ECU (electronic control unit) 10 .
  • a steering angle of the steering handle 6 is detected by a steering angle sensor 11 (see FIG. 4 ).
  • three turning mechanisms 12 (see FIG. 2 and FIG. 3 ), respectively corresponding to the three outboard motors 3 , are provided at the stern.
  • Each turning mechanism 12 includes an electric motor 102 (see FIG. 3 ) as a turning actuator driven in accordance with the steering angle detected by the steering angle sensor 11 .
  • the electric motors 102 of the three turning mechanisms 12 are controlled by a turning ECU 20 (see FIG. 4 ).
  • the steering apparatus 4 includes the steering handle 6 , the steering angle sensor 11 , the main ECU 10 , the turning ECU 20 , the three turning mechanisms 12 , three turning angle sensors 112 (see FIG. 3 and FIG. 4 ) to be described below, etc. Due to the turning angle of each outboard motor 3 being controlled by the steering apparatus 4 , a direction of the propulsive force is changed and a heading direction of the marine vessel 1 is changed accordingly.
  • the remote controller 7 includes two levers, i.e. right and left levers 7 P and 7 S. Each of these levers 7 P and 7 S can be inclined forward and rearward.
  • the lever disposed at a left side facing the stem shall be referred to as the “left lever 7 P” and the lever disposed at the right side facing the stem shall be referred to as the “right lever 7 S.”
  • Inclination positions of the levers 7 P and 7 S are respectively detected by potentiometers or other lever position sensors 13 P and 13 S (see FIG. 4 ).
  • the lever position sensor 13 P corresponds to the left lever 7 P and the lever position sensor 13 S corresponds to the right lever 7 S.
  • the display 9 displays states of the outboard motors 3 , an operation guidance screen, etc.
  • the operation panel 8 includes three key switches 81 P, 81 C, and 81 S (“key switch 81 ,” when referred to collectively below) respectively corresponding to the three outboard motors 3 P, 3 C, and 3 S.
  • the key switches 81 P, 81 C, and 81 S are switches that are operated to turn on and off power supplies to the outboard motors 3 P, 3 C, and 3 S, respectively, and to start the engines of the outboard motors 3 P, 3 C, and 3 S, respectively. Specifically, by operating a key switch 81 from an off position to an on position, the power supply to the corresponding outboard motor 3 can be turned on. Further, by operating the key switch 81 from the on position to the start position, the engine of the corresponding outboard motor 3 can be started. Also, by operating the key switch 81 from the on position to the off position, the power supply to the corresponding outboard motor 3 can be put in the off state.
  • FIG. 2 is a schematic side view for describing an arrangement example in common to the three outboard motors 3 .
  • Each outboard motor 3 includes a propulsion unit 60 and an attachment mechanism 61 to attach the propulsion unit 60 to the hull 2 .
  • the attachment mechanism 61 includes a clamp bracket 62 detachably fixed to a transom of the hull 2 and a swivel bracket 64 coupled to the clamp bracket 62 in a manner enabling pivoting around a tilt shaft 63 as a horizontal pivot axis.
  • the propulsion unit 60 is attached to the swivel bracket 64 in a manner enabling pivoting around a steering shaft 65 .
  • a turning angle (a direction angle defined by the direction of the propulsive force with respect to a centerline of the hull 2 ) can be changed by pivoting the propulsion unit 60 around the steering shaft 65 .
  • a trim angle of the propulsion unit 60 can be changed by pivoting the swivel bracket 64 around the tilt shaft 63 .
  • the trim angle is an angle of attachment of the outboard motor 3 with respect to the hull 2 .
  • a housing of the propulsion unit 60 includes a top cowling 66 , an upper case 67 , and a lower case 68 .
  • An engine 69 is installed as a drive source in the top cowling 66 with an axis of a crankshaft thereof extending vertically.
  • a driveshaft 91 for power transmission is coupled to a lower end of the crankshaft of the engine 69 and vertically extends through the upper case 67 into the lower case 68 .
  • a propeller 90 which is a propulsive force generating member, is rotatably attached to a rear side of a lower portion of the lower case 68 .
  • a propeller shaft 92 which is a rotation shaft of the propeller 90 , extends horizontally in the lower case 68 .
  • the rotation of the driveshaft 91 is transmitted to the propeller shaft 92 via a shift mechanism 93 , which is a clutch mechanism.
  • the shift mechanism 93 includes a drive gear 93 a , defined by a beveled gear fixed to a lower end of the driveshaft 91 , a forward drive gear 93 b , defined by a beveled gear rotatably disposed on the propeller shaft 92 , a reverse drive gear 93 c , likewise defined by a beveled gear rotatably disposed on the propeller shaft 92 , and a dog clutch 93 d disposed between the forward drive gear 93 b and the reverse drive gear 93 c.
  • the forward drive gear 93 b is meshed with the drive gear 93 a from a front side
  • the reverse drive gear 93 c is meshed with the drive gear 93 a from a rear side.
  • the forward drive gear 93 b and the reverse drive gear 93 c are thus rotated in mutually opposite directions.
  • the dog clutch 93 d is in spline engagement with the propeller shaft 92 . That is, the dog clutch 93 d is axially slidable with respect to the propeller shaft 92 , but is not rotatable relative to the propeller shaft 92 and thus rotates together with the propeller shaft 92 .
  • the dog clutch 93 d is slid along the propeller shaft 92 by axial pivoting of a shift rod 94 extending vertically parallel or substantially parallel to the driveshaft 91 .
  • the shift position of the dog clutch 93 d is thus controlled to be set at a forward drive position at which it is engaged with the forward drive gear 93 b , a reverse drive position at which it is engaged with the reverse drive gear 93 c , or a neutral position at which it is not engaged with either the forward drive gear 93 b or the reverse drive gear 93 c.
  • the reverse drive gear 93 c is rotated in a direction opposite to that of the forward drive gear 93 b , and the propeller 90 is thus rotated in an opposite direction (reverse drive direction) to generate a propulsive force in a direction of moving the hull 2 in reverse.
  • the dog clutch 93 d is at the neutral position, the rotation of the driveshaft 91 is not transmitted to the propeller shaft 92 . That is, transmission path of a driving force between the engine 69 and the propeller 90 is cut off so that a propulsive force is not generated in either direction.
  • a starter motor 45 is disposed to start the engine 69 .
  • the starter motor 45 is controlled by the outboard motor ECU 30 .
  • a throttle actuator 48 is provided to actuate a throttle valve 52 of the engine 69 to change a throttle opening degree and thus change an intake air amount of the engine 69 .
  • the throttle actuator 48 may include an electric motor.
  • the operation of the throttle actuator 48 is controlled by the outboard motor ECU 30 .
  • the engine 69 further includes an engine speed sensor 43 to detect the rotation of the crankshaft so as to detect the rotational speed of the engine 69 .
  • a shift actuator 49 to change the shift position of the dog clutch 93 d is provided.
  • the shift actuator 49 includes, for example, an electric motor, and operation thereof is controlled by the outboard motor ECU 30 .
  • a shift position sensor 44 that detects the shift position of the shift mechanism 93 is provided.
  • the turning mechanism 12 is coupled to a steering arm 97 fixed to the propulsion unit 60 .
  • the propulsion unit 60 is pivoted to the right and left around the steering shaft 65 and steering of the marine vessel 1 can thus be performed.
  • FIG. 3 is an arrangement diagram of an arrangement of the turning mechanism.
  • the turning mechanism 12 is preferably a hydraulic turning mechanism.
  • the turning mechanism 12 includes a hydraulic pump 101 , an electric motor 102 to drive the hydraulic pump 101 , and a hydraulic cylinder 103 .
  • the hydraulic cylinder 103 is preferably a double-rod type double acting cylinder.
  • the hydraulic cylinder 103 includes a cylinder tube 104 , a piston 105 provided inside the cylinder tube 104 , and a piston rod 106 connected to the piston 105 .
  • the cylinder tube 104 and the piston rod 106 extend in a right/left direction.
  • a space inside the cylinder tube 104 is partitioned by the piston 105 into a first cylinder chamber 107 at the left side and a second cylinder chamber 108 at the right side.
  • the piston 105 is capable of moving relatively to the right and left inside the cylinder tube 104 .
  • the right/left position of the piston 105 is fixed with respect to the hull 2 and the cylinder tube 104 moves to the right and left with respect to the piston 105 .
  • the first cylinder chamber 107 is connected to a first port of the hydraulic pump 101 via a first oil passage 109 .
  • the second cylinder chamber 108 is connected to a second port of the hydraulic pump 101 via a second oil passage 110 .
  • One end portion and another end portion of the piston rod 106 respectively project axially outward from one end portion and another end portion of the cylinder tube 104 .
  • the one end portion and the other end portion of the piston rod 106 are respectively coupled to two fixed arms 111 .
  • the two fixed arms 111 are fixed to the swivel bracket 64 .
  • the piston rod 106 is thus attached to the hull 2 via the swivel bracket 64 and the clamp bracket 62 (see FIG. 2 ).
  • the cylinder tube 104 is coupled to the steering arm 97 fixed to the outboard motor 3 .
  • the cylinder tube 104 is guided by the piston rod 106 and is thus enabled to move in the right and left directions with respect to the hull 2 .
  • the outboard motor 3 pivots to the right and left around the steering shaft 65 in accompaniment with the movement of the cylinder tube 104 in the right and left directions.
  • a turning angle midpoint of an outboard motor 3 is a position of the outboard motor 3 at which a rotation axis Ap of the propeller 90 of the outboard motor 3 is parallel or substantially parallel to a straight line extending in a front/rear direction of the hull 2 in a plan view.
  • a position of the cylinder tube 104 with respect to the hull 2 when the outboard motor 3 is positioned at the turning angle midpoint shall be referred to as the turning angle midpoint position of the cylinder tube 104 .
  • the turning angle sensor 112 to detect the actual turning angle of the outboard motor 3 is provided in a vicinity of the hydraulic cylinder 103 .
  • the turning angle sensor 112 detects an amount of movement of the cylinder tube 104 in both the right and left directions from the turning angle midpoint position of the cylinder tube 104 .
  • the turning angle sensor 112 for example, outputs the amount of movement of the cylinder tube 104 in the left direction from the turning angle midpoint position as a positive value and outputs the amount of movement in the right direction from the turning angle midpoint position as a negative value.
  • the turning angle of the outboard motor 3 is detected based on the movement amount of the cylinder tube 104 from the turning angle midpoint position that is detected by the turning angle sensor 112 .
  • the turning angle sensor corresponding to the port outboard motor 3 P shall be referred to as the “turning angle sensor 112 P”
  • the turning angle sensor corresponding to the central outboard motor 3 C shall be referred to as the “turning angle sensor 112 C”
  • the turning angle sensor corresponding to the starboard outboard motor 3 S shall be referred to as the “turning angle sensor 112 S.”
  • a first pilot check valve 113 is provided in a middle of the first oil passage 109 .
  • a second pilot check valve 114 is provided in a middle of the second oil passage 110 .
  • a pilot port of the first pilot check valve 113 is connected to a portion in the second oil passage 110 between the hydraulic pump 101 and the second pilot check valve 114 .
  • a pilot port of the second pilot check valve 114 is connected to a portion in the first oil passage 109 between the hydraulic pump 101 and the first pilot check valve 113 .
  • the first pilot check valve 113 and the second pilot check valve 114 allow oil to flow through from the hydraulic pump 101 side to the hydraulic cylinder 103 side and blocks the flow of oil from the hydraulic cylinder 103 side to the hydraulic pump 101 side. However, each of the pilot check valves 113 and 114 is put in a state enabling reverse flow (flow through of oil from the hydraulic cylinder 103 side to the hydraulic pump 101 side) when a pilot pressure thereof become no less than a predetermined value.
  • the first oil passage 109 and the second oil passage 110 are connected, at portions closer to the hydraulic cylinder 103 than to the pilot check valves 113 and 114 , by a bypass oil passage 116 including a bypass valve 115 .
  • the bypass valve 115 is a manually opened/closed bypass valve that is opened and closed manually and is normally in a closed state.
  • the first port of the hydraulic pump 101 is further connected via a first check valve 117 to an oil tank 121 and connected via a first relief valve 118 to the oil tank 121 .
  • the second port of the hydraulic pump 101 is connected via a second check valve 119 to the oil tank 121 and connected via a relief valve 120 to the oil tank 121 .
  • the electric motor 102 is driven to rotate in a forward rotation direction or a reverse rotation direction to drive the hydraulic pump 101 .
  • an output shaft of the electric motor 102 is coupled to an input shaft of the hydraulic pump 101 and by rotation of the output shaft of the electric motor 102 , the input shaft of the hydraulic pump 101 is rotated to achieve driving of the hydraulic pump 101 .
  • the electric motor 102 is, for example, a DC motor.
  • the electric motor corresponding to the port outboard motor 3 P shall be referred to as the “electric motor 102 P”
  • the electric motor corresponding to the central outboard motor 3 C shall be referred to as the “electric motor 102 C”
  • the electric motor corresponding to the starboard outboard motor 3 S shall be referred to as the “electric motor 102 S.”
  • the hydraulic pump 101 When the electric motor 102 is rotated in the forward rotation direction, the hydraulic pump 101 is rotated forwardly and, for example, oil inside the oil tank 121 is sucked into the hydraulic pump 101 via the second check valve 119 and discharged from the hydraulic pump 101 to the first oil passage 109 .
  • the oil discharged to the first oil passage 109 is supplied via the first pilot check valve 113 and the first oil passage 109 to the first cylinder chamber 107 of the hydraulic cylinder 103 .
  • the cylinder tube 104 is thus moved in the left direction with respect to the hull 2 so that a volume of the first cylinder chamber 107 increases.
  • the pilot pressure input into the second pilot check valve 114 becomes no less than the predetermined pressure and thus the second pilot check valve 114 is put in the state enabling reverse flow.
  • the oil inside the second cylinder chamber 108 is thus sucked via the second oil passage 110 and the second pilot check valve 114 into the hydraulic pump 101 .
  • the hydraulic pump 101 When the electric motor 102 is rotated in the reverse rotation direction, the hydraulic pump 101 is rotated reversely and the oil inside the oil tank 121 is sucked into the hydraulic pump 101 via the first check valve 117 and discharged from the hydraulic pump 101 to the second oil passage 110 .
  • the oil discharged to the second oil passage 110 is supplied via the second pilot check valve 114 and the second oil passage 110 to the second cylinder chamber 108 of the hydraulic cylinder 103 .
  • the cylinder tube 104 is thus moved in the right direction with respect to the hull 2 so that a volume of the second cylinder chamber 108 increases. Due to this process, the pilot pressure input into the first pilot check valve 113 becomes no less than the predetermined pressure and thus the first pilot check valve 113 is put in the state enabling reverse flow.
  • the oil inside the first cylinder chamber 107 is thus sucked via the first oil passage 109 and the first pilot check valve 113 into the hydraulic pump 101 .
  • FIG. 4 is a diagram for describing an electrical arrangement of a principal portion of the marine vessel 1 .
  • the operation panel 8 , the display 9 , the steering angle sensor 11 , and the lever position sensors 13 P and 13 S are connected to the main ECU 10 .
  • the main ECU 10 includes a computer (microcomputer).
  • the main ECU 10 is connected to a bus 15 that defines an inboard LAN (local area network).
  • a speed sensor 14 to detect a speed of the marine vessel 1 is connected to the bus 15 .
  • the outboard motors 3 S, 3 C, and 3 P include outboard motor ECUs 30 S, 30 C, and 30 P, respectively.
  • the outboard motor ECU 30 P corresponds to the port outboard motor 3 P
  • the outboard motor ECU 30 C corresponds to the central outboard motor 3 C
  • the outboard motor ECU 30 S corresponds to the starboard outboard motor 3 S.
  • the outboard motor ECUs 30 S, 30 C, and 30 P are connected to the bus 15 .
  • the outboard motor ECUs 30 S, 30 C, and 30 P are practically the same in internal arrangement and shall be referred to as the “outboard motor ECU 30 ” when referred to collectively below.
  • Each outboard motor ECU 30 includes a computer (microcomputer).
  • the starter motor 45 is a device to perform cranking of the engine.
  • the injector 47 is a device that injects fuel into an air intake path of the engine.
  • the throttle actuator 48 is a device that controls the throttle valve 52 to adjust the amount of air supplied to the air intake path of the engine.
  • the ignition coil 46 is a device that increases a voltage applied to a spark plug (not shown).
  • the spark plug is a device that discharges inside a combustion chamber of the engine to ignite a mixed gas inside the combustion chamber.
  • the shift actuator 49 is a device that drives the shift mechanism 93 of the outboard motor.
  • the fuel pump 50 is a device that pumps out fuel from a fuel tank (not shown) to supply the fuel to the injector 47 .
  • the oil pump 51 is a device that circulates engine oil inside the engine.
  • the temperature sensor 41 detects a temperature of cooling water in the engine.
  • the hydraulic pressure sensor 42 detects a pressure of the engine oil.
  • the engine speed sensor 43 detects the rotational speed of the engine.
  • the shift position sensor 44 detects the shift position of the shift mechanism 93 (shift position of the outboard motor).
  • the electric motors 102 P, 102 C, and 102 S and the turning angle sensors 112 P, 112 C, and 112 S of the turning mechanisms 12 respectively corresponding to the outboard motors 30 P, 30 C, and 30 S are connected to the turning ECU 20 .
  • the turning ECU 20 is connected to the bus 15 .
  • the turning ECU 20 includes drive circuits to drive the respective electric motors 102 P, 102 C, and 102 S and a computer (microcomputer) to control the drive circuits.
  • the computer of the main ECU 10 executes programs to achieve the functions of a plurality of function processing units.
  • the function processing units include an electric power supply/starting control unit, a shift position etc., computing unit, a basic target turning angle computing unit, and a malfunction operation control unit.
  • Functions of the main ECU 10 as the electric power supply/starting control unit include performing, on the basis of an operation signal from a key switch 81 on the operation panel 8 , on/off control of the electric power supply of the corresponding outboard motor 3 and starting control of the engine of the corresponding outboard motor 3 .
  • Functions of the main ECU 10 as the shift position etc., computing unit include performing a shift position etc., computing process of computing target shift positions and target engine speeds of the respective outboard motors 3 based on outputs of the lever position sensors 13 P and 13 S.
  • Functions of the main ECU 10 as the basic target turning angle computing unit include performing a basic target turning angle computing process of computing basic target turning angles of the respective outboard motors 3 based on an output of the steering angle sensor 11 .
  • Functions of the main ECU 10 as the malfunction operation control unit include performing a malfunction operation control process when there is a malfunction in the turning angle control of any of the outboard motors 3 .
  • the functions of the main ECU 10 as the electric power supply/starting control unit areas follows. That is, when a key switch 81 is operated from the off position to the on position, the main ECU 10 turns on the electric power supply of the corresponding outboard motor ECU 30 . Also, when the key switch 81 is operated from the on position to the off position, the main ECU 10 turns off the electric power supply of the corresponding outboard motor 3 . Also, when the key switch 81 is operated from the on position to the start position, the main ECU 10 outputs an engine starting command to the corresponding outboard motor ECU 30 under a condition that the starting allowing conditions are met.
  • the starting allowing conditions include the target shift position of the outboard motor 3 , computed by the main ECU 10 , is the neutral position and the actual shift position of the shift mechanism 93 of the corresponding outboard motor 3 is the neutral position.
  • Information on the shift position of the shift mechanism 93 of each outboard motor 3 is sent from the corresponding outboard motor ECU 30 to the main ECU 10 via the bus 15 .
  • the outboard motor ECU 30 Upon receiving the engine starting command, the outboard motor ECU 30 performs an engine starting process. In the engine starting process, the outboard motor ECU 30 drives the starter motor 45 , the ignition coil 46 , and the injector 47 to perform fuel supply control and ignition control to start the engine.
  • the main ECU 10 Based on the output signals of the lever position sensors 13 S and 13 P, the main ECU 10 computes the target shift positions and the target engine speeds for the respective outboard motors 3 and transmits these to the corresponding outboard motor ECUs 30 .
  • Each outboard motor ECU 30 controls the shift position and the engine speed of the corresponding outboard motor 3 based on the target shift position and the target engine speed that are transmitted from the main ECU 10 .
  • the outboard motor ECU 30 controls the shift actuator 49 so that the shift position of the outboard motor 3 becomes the target shift position and controls the throttle actuator 48 so that the engine speed becomes the target engine speed.
  • each outboard motor 3 is controlled as follows.
  • the left lever 7 P is associated with the port outboard motor 3 P
  • the right lever 7 S is associated with the starboard outboard motor 3 S
  • both levers 7 P and 7 S are associated with the central outboard motor 3 C.
  • the shift position of the port outboard motor 3 P is set to the forward drive position and a propulsive force in the forward drive direction is generated from the corresponding outboard motor 3 P.
  • the target engine speed is set at an idling engine speed up to the inclination position of the predetermined amount (forward drive shift-in position).
  • the target engine speed increases as the lever inclination amount increases.
  • the shift position of the port outboard motor 3 P is set at the reverse drive position and a propulsive force in the reverse drive direction is generated from the port outboard motor 3 P.
  • the target engine speed is set at the idling engine speed up to the inclination position of the predetermined amount (reverse drive shift-in position).
  • the target engine speed increases as the lever inclination amount increases.
  • the shift position of the port outboard motor 3 P is set at the neutral position and the outboard motor 3 P does not generate a propulsive force.
  • the shift position of the central outboard motor 3 C is controlled as follows according to the operations of both levers 7 P and 7 S. That is, when the levers 7 P and 7 S are both inclined forward to no less than the forward drive shift-in positions from the neutral positions, the shift position of the central outboard motor 3 C is set at the forward drive position and a propulsive force in the forward drive direction is generated from the central outboard motor 3 C. When the levers 7 P and 7 S are both inclined rearward to no less than the reverse drive shift-in positions from the neutral positions, the shift position of the central outboard motor 3 C is controlled to be at the reverse drive position and a propulsive force in the reverse drive direction is generated from the central outboard motor 3 C.
  • the target engine speed is set to the idling engine speed if the inclination positions of both levers 7 P and 7 S are between the forward drive shift-in positions and the reverse drive shift-in positions.
  • the target engine speed is set according to the inclination amounts of both levers 7 P and 7 S.
  • the shift position of the central outboard motor 3 C is set at the neutral position.
  • the shift position of the central outboard motor 3 C is also set at the neutral position when one of the levers is inclined forward from the neutral position (for example, inclined forward relative to the forward drive shift-in position) and the other lever is inclined rearward from the neutral position (for example, inclined rearward relative to the reverse drive shift-in position).
  • FIGS. 5A-5F are schematic views for describing relationships of the respective lever positions and movements of a hull.
  • the shift position of the port outboard motor 3 P is set at the forward drive position and the shift positions of the other outboard motors 3 C and 3 S are set at the neutral positions.
  • the hull 2 thus receives only the forward drive direction propulsive force of the port outboard motor 3 P and thus turns in the right direction.
  • the shift position of the starboard outboard motor 3 S is set at the forward drive position and the shift positions of the other outboard motors 3 P and 3 C are set at the neutral positions.
  • the hull 2 thus receives only the forward drive direction propulsive force of the starboard outboard motor 3 S and thus turns in the left direction.
  • both levers 7 P and 7 S are inclined forward (to the F side) relative to the neutral positions, the shift positions of all three outboard motors 3 are set at the forward drive positions.
  • the hull 2 is thus driven forward by the forward drive direction propulsive forces of all three outboard motors 3 .
  • both levers 7 P and 7 S are inclined rearward (to an R side) relative to the neutral positions, the shift positions of all three outboard motors 3 are set at the reverse drive positions.
  • the hull 2 is thus driven in reverse by the reverse drive direction propulsive forces of all three outboard motors 3 .
  • FIG. 5E shows a state where the left lever 7 P is inclined rearward (to the R side) relative to the neutral position and the right lever 7 S is inclined forward (to the F side) relative to the neutral position.
  • the shift position of the port outboard motor 3 P is set at the reverse drive position
  • the shift position of the starboard outboard motor 3 S is set at the forward drive position
  • the shift position of the central outboard motor 3 C is set at the neutral position.
  • the hull 2 is thus turned to the left by the reverse drive direction propulsive force of the port outboard motor 3 P and the forward drive direction propulsive force of the starboard outboard motor 3 S.
  • FIG. 5F shows a state where the left lever 7 P is inclined forward (to the F side) relative to the neutral position and the right lever 7 S is inclined rearward (to the R side) relative to the neutral position.
  • the shift position of the port outboard motor 3 P is set at the forward drive position
  • the shift position of the starboard outboard motor 3 S is set at the reverse drive position
  • the shift position of the central outboard motor 3 C is set at the neutral position.
  • the hull 2 is thus turned to the right by the forward drive direction propulsive force of the port outboard motor 3 P and the reverse drive direction propulsive force of the starboard outboard motor 3 S.
  • main ECU 10 as the basic target turning angle computing unit and as the malfunction operation control unit shall be described below.
  • each outboard motor ECU 30 executes programs to achieve the functions of a plurality of function processing units.
  • the plurality of function processing units include an engine starting process unit, a shift control unit, etc.
  • a function of the outboard motor ECU 30 as the engine starting process unit is to perform the engine starting process.
  • a function of the outboard motor ECU 30 as a shift control unit is to control the engine speed and the shift position based on the target engine speed and the target shift position computed by the main ECU 10 .
  • the computer of the turning ECU 20 executes programs to achieve the functions of a plurality of function processing units.
  • the plurality of function processing units include a motor control unit, a malfunction monitoring unit, etc.
  • a function of the turning ECU 20 as the motor control unit is to perform a motor control process to control the electric motors 102 of the turning mechanisms 12 of the respective outboard motors 3 based on the basic target turning angle computed by the main ECU 10 .
  • a function of the turning ECU 20 as the malfunction monitoring unit is to monitor whether or not there is a malfunction in the turning angle control of the respective outboard motors 3 .
  • FIG. 6 is a flowchart of procedures of the basic target turning angle computing process performed by the main ECU 10 and procedures of the motor control process performed by the turning ECU 20 .
  • the reference target turning angle computing process and the motor control process shown in FIG. 6 are performed repeatedly at every predetermined computation cycle.
  • the main ECU 10 acquires a steering angle ⁇ based on the output of the steering angle sensor 11 (step S 1 ).
  • the main ECU 10 then computes a basic target turning angle ⁇ o* in common to all of the outboard motors 3 based on the acquired steering angle ⁇ and transmits it to the turning ECU 20 (step S 2 ).
  • the main ECU 10 for example, computes the basic target turning angle ⁇ o* corresponding to the acquired steering angle ⁇ based on a map by which a relationship of the steering angle ⁇ and the basic target turning angle ⁇ o* is stored in advance.
  • the turning ECU 20 Upon receiving the basic target turning angle ⁇ o* transmitted from the main ECU 10 (step S 11 : YES), the turning ECU 20 computes target turning angles ⁇ * of the respective outboard motors 3 based on the received basic target turning angle ⁇ o* (step S 12 ). For example, the turning ECU 20 computes the target turning angles ⁇ * of the respective outboard motors 3 corresponding to the received basic target turning angle ⁇ o* based on a map by which a relationship of the basic target turning angle ⁇ o* and the target turning angles ⁇ * of the respective outboard motors 3 is stored in advance. The turning ECU 20 may use the received basic target turning angle ⁇ o* as it is as the target turning angle ⁇ * of each outboard motor 3 .
  • the turning ECU 20 uses the target turning angle ⁇ * of each outboard motor 3 to perform feedback control of the electric motor 102 of the turning mechanism 12 of the corresponding outboard motor 3 (step S 13 ). Specifically, the turning ECU 20 drives the electric motor 102 of the turning mechanism 12 of each outboard motor 3 so that the actual turning angle ⁇ of the corresponding outboard motor 3 detected by the turning angle sensor 112 approaches the target turning angle ⁇ * of the corresponding outboard motor 3 . The turning angles of the respective outboard motors 3 are thus controlled in accordance with the steering angle of the steering handle 6 .
  • the steering ECU 20 As the malfunction monitoring unit are as follows. When in a certain outboard motor 3 there is a malfunction of the turning mechanism 12 or the turning angle sensor 112 , the actual turning angle ⁇ corresponding to the outboard motor 3 does not converge to the target turning angle ⁇ * corresponding to the outboard motor 3 .
  • the turning ECU 20 thus monitors, for each outboard motor 3 , whether or not a state where a difference between the actual turning angle ⁇ and the target turning angle ⁇ * is greater than a predetermined value has continued for no less than a predetermined time.
  • the turning ECU 20 judges that there is a malfunction in the turning angle control of the outboard motor 3 and provides notification of this condition to the main ECU 10 .
  • FIG. 7A , FIG. 7B , and FIG. 7C are flowcharts of procedures of the malfunction operation control process executed by the main ECU 10 .
  • the main ECU 10 monitors whether or not there is a malfunction in the turning angle control of each outboard motor 3 (step S 21 ).
  • Malfunctions in the turning angle control of an outboard motor 3 include a malfunction of the steering angle sensor 11 , a malfunction of the turning mechanism 12 , a malfunction of the turning angle sensor 112 , etc.
  • a malfunction of the steering angle sensor 11 is included among malfunctions due to an input system in common to all turning mechanisms 12 .
  • a malfunction of the turning mechanism 12 or a malfunction of the turning angle sensor 112 is included among malfunctions due to output systems of the respective turning mechanisms 12 .
  • the output signal of the steering angle sensor 11 is fixed at a predetermined value.
  • the main ECU 10 can thus detect the malfunction of the steering angle sensor 11 (including disconnection of a signal line of the steering angle sensor 11 ) by monitoring the output signal of the steering angle sensor 11 .
  • the malfunction of the steering angle sensor 11 is detected, the turning angle control of none of the outboard motors 3 can be performed and thus the main ECU 10 judges that there is a malfunction in the turning angle control of all of the outboard motors 3 .
  • a notification of this condition is provided from the turning ECU 20 to the main ECU 10 as mentioned above.
  • the main ECU 10 can thus detect that there is a malfunction in the turning angle control of any of the outboard motors 3 and can recognize the outboard motor 3 with the malfunction in the turning angle control.
  • step S 21 Upon detecting that there is a malfunction in the turning angle control of any of the outboard motors 3 among the three outboard motors 3 (step S 21 : YES), the main ECU 10 enters step S 22 .
  • step S 22 the main ECU 10 judges whether there is a malfunction in the turning angle control of all outboard motors 3 or there is a malfunction in the turning angle control of one of the outboard motors 3 and stores the judgment result (step S 22 ).
  • the main ECU 10 performs a process to forcibly decelerate a traveling speed of the marine vessel 1 (this process may hereinafter be referred to at times as the “forced deceleration process”) (step S 23 ). Specifically, the main ECU 10 fixes the target engine speeds for all outboard motors 3 at a predetermined speed regardless of the positions of the levers 7 P and 7 S and fixes the target shift positions for all outboard motors 3 at the neutral positions regardless of the positions of the levers 7 P and 7 S.
  • the predetermined speed is set, for example, to an idling engine speed.
  • the fixing of the target engine speed at the predetermined speed may also be performed by forcibly closing the throttle valves 52 fully.
  • each outboard motor ECU 30 a control of setting the engine speed of the corresponding outboard motor 3 at the predetermined speed and a control of setting the shift position of the corresponding outboard motor 3 at the neutral position are performed.
  • the power transmission between the engine 69 and the propeller 90 is thus interrupted in all outboard motors 3 so that the generation of a propulsive force by all outboard motors 3 is stopped and the traveling speed of the marine vessel 1 is decelerated.
  • the main ECU 10 displays, on the display 9 , an operation guidance screen to urge the marine vessel operator to operate the levers 7 P and 7 S to the neutral positions (step S 24 ).
  • An example of the operation guidance screen displayed on the display in step S 24 is shown in FIG. 8 .
  • the operation guidance screen includes the emergency message: “There is a turning angle control malfunction.” and the operation guidance: “Operate the levers to the neutral positions.”
  • the main ECU 10 waits for the levers 7 P and 7 S to be operated to the neutral positions (step S 25 ). Whether or not the levers 7 P and 7 S have been operated to the neutral positions is judged based on the output signals of the lever position sensors 13 P and 13 S.
  • FIGS. 11A-11C are schematic views for specifically describing the process of steps S 21 to S 25 .
  • the main ECU 10 performs the “forced deceleration process.”
  • the engine speeds of all outboard motors 3 are thus set at the predetermined speed regardless of the positions of the levers 7 P and 7 S and the shift positions of all outboard motors 3 are set at the neutral positions as shown in FIG. 11B .
  • the main ECU 10 displays the operation guidance screen, such as shown in FIG. 8 , on the display 9 .
  • the marine vessel operator operates the levers 7 P and 7 S to the neutral positions as shown in FIG. 11C in accordance with the operation guidance screen.
  • step S 24 When after the operation guidance screen (see FIG. 8 ) has been displayed in step S 24 , the levers 7 P and 7 S are operated to the neutral positions by the marine vessel operator (step S 25 of FIG. 7A : YES), the main ECU 10 ends the “forced deceleration process” that is currently being performed and restarts the normal shift position etc., computing process (step S 26 ).
  • the target engine speeds and the target shift positions computed in accordance with the positions of the lever 7 P and 7 S are thus transmitted to the respective outboard motor ECUs 30 .
  • the main ECU 10 restricts the engine speeds of all outboard motors 3 to no more than a predetermined first restriction speed (step S 29 ). Specifically, the main ECU 10 restricts the target engine speeds transmitted to all outboard motor ECUs 30 to no more than the predetermined first restriction speed. More specifically, in a case where a target engine speed computed based on the positions of the lever 7 P and 7 S is higher than the first restriction speed, the main ECU 10 restricts the target engine speed to the first restriction speed. The propulsive forces of all outboard motors 3 are thus restricted.
  • the main ECU 10 displays, on the display 9 , an operation guidance screen to notify the marine vessel operator that there is a malfunction in the turning angle control of all outboard motors 3 and that steering should be performed by operating the levers 7 P and 7 S (step S 30 ).
  • An example of the operation guidance screen displayed on the display 9 in step S 29 is shown in FIG. 9 .
  • the operation guidance screen includes the emergency message: “There is a turning angle control malfunction,” the character string: “All outboard motors” indicating that there is a malfunction in the turning angle control of all outboard motors, and the operation guidance: “Perform steering by operating the levers.”
  • the marine vessel operator recognizes that there is a malfunction in the turning angle control of all outboard motors and that steering should be performed by operating the levers 7 P and 7 S.
  • the marine vessel operator thus judges whether or not the turning angles of all outboard motors 3 are near the respective turning angle midpoints (step S 31 ). If the marine vessel operator judges that the turning angles of all outboard motors 3 are not near the turning angle midpoints (step S 31 : NO), he/she performs the following operation.
  • the marine vessel operator opens the bypass valves 115 of the turning mechanisms 12 corresponding to all outboard motors 3 , moves all outboard motors 3 to the respective turning angle midpoints manually and thereafter closes the bypass valves 115 of the turning mechanisms 12 corresponding to all outboard motors 3 (step S 32 ).
  • the turning angles of all outboard motors 3 are thus fixed near the turning angle midpoints.
  • the marine vessel operator operates the levers 7 P and 7 S to steer the marine vessel 1 (step S 33 ).
  • step S 31 If the marine vessel operator judges that the turning angles of all outboard motors 3 are near the turning angle midpoints (step S 31 : YES), the marine vessel operator steers the marine vessel 1 by lever operations without performing the operation of step S 32 (step S 33 ).
  • step S 33 a turning operation of the marine vessel 1 by generation of a propulsive force at no less than one of the outboard motors 3 is performed in the state where the turning angles of all outboard motors 3 are fixed near the turning angle midpoints. That is, the turning operation of the marine vessel 1 is performed by output differences among the outboard motors 3 .
  • the turning operation of the marine vessel 1 is performed by the lever operations described in FIG. 5A , FIG. 5B , FIG. 5E , and FIG. 5F .
  • a turning performance of the marine vessel 1 can thus be secured even when there is a malfunction in the turning angle control of all outboard motors 3 .
  • the propulsive forces of the outboard motors 3 become too great due to turning the marine vessel 1 by making use of the propulsive forces of the outboard motors 3 without performing turning angle control of the outboard motors 3 , it may be difficult to obtain a turning behavior intended by the marine vessel operator.
  • the engine speeds of all outboard motors 3 are restricted to no more than the predetermined first restriction speed in step S 29 . The propulsive forces of the outboard motors 3 can thus be prevented from becoming too large and the turning behavior intended by the marine vessel operator can be obtained readily.
  • step S 30 an operation guidance for making all outboard motors 3 move to the turning angle midpoints may be displayed in the operation guidance screen.
  • all outboard motors 3 may be forcibly controlled respectively to move to the turning angle midpoints automatically.
  • step S 34 the main ECU 10 stops the turning angle control of the outboard motor 3 with the turning angle control malfunction (hereinafter referred to as the “malfunctioning outboard motor”). Specifically, the main ECU 10 transmits a turning angle control stopping command to stop the turning angle control of the malfunctioning outboard motor 3 to the turning ECU 20 . Upon receiving the turning angle control stopping command, the turning ECU 20 stops the motor control process for the turning mechanism 12 of the malfunctioning outboard motor 3 . The malfunctioning outboard motor 3 is thus put in a state where the turning angle control is not performed.
  • the main ECU 10 displays, on the display 9 , an operation guidance screen to urge the marine vessel operator to open the bypass valve of the turning mechanism 12 corresponding to the outboard motor 3 with the turning angle control malfunction (step S 35 ).
  • An example of the operation guidance screen displayed on the display 9 in step S 35 is shown in FIG. 10 .
  • the operation guidance screen includes the emergency message: “There is a turning angle control malfunction,” the character string: “Starboard outboard motor” indicating that there is a malfunction in the turning angle control of the starboard outboard motor, and the operation guidance: “Open the bypass valve of the malfunctioning outboard motor.”
  • the main ECU 10 performs a process to forcibly stop the generation of a propulsive force by the malfunctioning outboard motor 3 (hereinafter referred to at times as the “malfunctioning outboard motor propulsive force stopping process”) (step S 36 ). Specifically, the main ECU 10 fixes the target engine speed for the malfunctioning outboard motor 3 at a predetermined idle engine speed regardless of the positions of the levers 7 P and 7 S and fixes the target shift position for the malfunctioning outboard motor 3 at the neutral position regardless of the positions of the levers 7 P and 7 S.
  • the outboard motor ECU 30 corresponding to the malfunctioning outboard motor 3 a control of setting the engine speed of the malfunctioning outboard motor 3 at the idle engine speed and a control of setting the shift position of the malfunctioning outboard motor 3 at the neutral position are performed.
  • the power transmission between the engine 69 and the propeller 90 is thus interrupted at the malfunctioning outboard motor 3 so that the generation of a propulsive force by the malfunctioning outboard motor 3 is stopped regardless of the positions of the levers 7 P and 7 S.
  • the engine speed of the malfunctioning outboard motor 3 is set at the idle engine speed to prevent wasteful fuel consumption.
  • the outboard motor ECU 30 corresponding to the malfunctioning outboard motor 3 keeps the shift position of the malfunctioning outboard motor 3 at the neutral position regardless of the positions of the levers 7 P and 7 S.
  • the malfunctioning outboard motor 3 is thus kept in the state where the power transmission between the engine 69 and the propeller 90 is interrupted.
  • the main ECU 10 restricts the engine speeds of the other normally functioning outboard motors 3 (the outboard motors without a malfunction in the turning angle control) to no more than a predetermined second restriction speed (step S 37 ). Specifically, the main ECU 10 restricts the target engine speeds transmitted to the other normally functioning outboard motors 3 to no more than the predetermined second restriction speed. More specifically, in a case where a target engine speed for a normally functioning outboard motor 3 computed based on the positions of the lever 7 P and 7 S is higher than the second restriction speed, the main ECU 10 restricts the target engine speed to the second restriction speed.
  • the marine vessel operator recognizes that there is a malfunction in the turning angle control of one of the outboard motors 3 and that the bypass valve 115 of the turning mechanism 12 corresponding to the malfunctioning outboard motor 3 should be opened.
  • the marine vessel operator thus opens the bypass valve 115 of the turning mechanism 12 corresponding to the malfunctioning outboard motor 3 (step S 38 ).
  • the malfunctioning outboard motor 3 is thus put in a freely turning state of pivoting freely in the right and left directions even though the turning angle control thereof cannot be performed.
  • the malfunctioning outboard motor 3 is thus put in a state of being pivotable under the influence of an external force due to the other adjacent outboard motors 3 or by a water stream.
  • step S 34 the turning angle control of the malfunctioning outboard motor 3 is kept in the stopped state by step S 34 .
  • the hydraulic cylinder 103 is not actuated by the driving of the electric motor 102 of the corresponding turning mechanism 12 because the bypass valve 115 of the turning mechanism 12 corresponding to the malfunctioning outboard motor 3 is open.
  • the marine vessel operator then steers the marine vessel 1 by operating the steering handle 6 while the bypass valve 115 is kept in the open state (step S 39 ).
  • the turning mechanisms 12 corresponding to the normally functioning outboard motors 3 are kept in states of being capable of turning the corresponding outboard motors 3 (normal states) and thus the turning angle control of the normally functioning outboard motors 3 is performed as is done normally.
  • the turning performance of the marine vessel 1 can thus be secured by the turning angle control of the normally functioning outboard motors 3 .
  • the malfunctioning outboard motor 3 is put in the state where the generation of a propulsive force is stopped and is put in the freely turning state.
  • the malfunctioning outboard motor 3 is turned in the same direction as the other normally functioning outboard motors 3 so as to follow a water stream generated in a periphery thereof.
  • a possibility of a normally functioning outboard motor 3 contacting the malfunctioning outboard motor 3 when the turning angle control of the normally functioning outboard motors 3 is performed is thus low. Also, even if a normally functioning outboard motor 3 contacts the malfunctioning outboard motor 3 , a load due to the contact is small.
  • the propulsive force due to the malfunctioning outboard motor 3 is stopped and thus the marine vessel 1 travels at a lower vessel speed than a vessel speed due to a maximum propulsive force that can be generated from all outboard motors 3 .
  • the load in the case where a normally functioning outboard motor 3 contacts the malfunctioning outboard motor 3 is thus significantly reduced.
  • the engine speeds of the normally functioning outboard motors 3 are restricted to no more than the second restriction speed in step S 37 and thus the load in the case where a normally functioning outboard motor 3 contacts the malfunctioning outboard motor 3 can be reduced even further.
  • the operation guidance screen that provides notification that the levers 7 P and 7 S should be operated to the neutral positions is displayed in step S 24 of FIG. 7A .
  • the operation guidance screen corresponding to the case where there is a malfunction in the turning angle control of all outboard motors 3 is displayed in step S 30 of FIG. 7B and the operation guidance screen corresponding to the case where there is a malfunction in the turning angle control of one of the outboard motors 3 (see FIG. 10 ) is displayed in step S 35 of FIG. 7C .
  • the contents of the operation guidance screen of FIG. 9 or the contents of the operation guidance screen of FIG. 10 may be included, in accordance with the judgment result of step S 22 of FIG. 7A , in the operation guidance screen of FIG. 8 displayed in step S 24 of FIG. 7A .
  • the engine speeds of all outboard motors 3 preferably are restricted to no more than the predetermined first restriction speed in step S 29 of FIG. 7B , this process may be omitted.
  • the target engine speed for the malfunctioning outboard motor 3 is fixed at the predetermined idling engine speed and the target shift position for the malfunctioning outboard motor 3 is fixed at the neutral position in step S 36 of FIG. 7B .
  • the target shift position for the malfunctioning outboard motor 3 may be fixed at the neutral position without fixing the target engine speed for the malfunctioning outboard motor 3 at the predetermined idling engine speed.
  • the engine speeds of the other normally functioning outboard motors 3 are preferably restricted to no more than the predetermined second restriction speed in step S 37 of FIG. 7B , this process may be omitted.
  • bypass valve 115 preferably is a manually opened/closed bypass valve, it may instead be an automatically opened/closed bypass valve that is opened and closed by electric power.
  • the turning mechanisms 12 of the three outboard motors 3 are preferably controlled by a single turning ECU 20 in common thereto, the turning mechanisms 12 may instead be controlled by a plurality of turning ECUs provided in respective correspondence to the plurality of outboard motors 3 .
  • each outboard motor preferably is an engine
  • the motor of each outboard motor may instead be an electric motor.
  • the turning mechanism 12 preferably is arranged to control the turning direction of the outboard motor by the rotation direction of the hydraulic pump 101
  • a directional control valve driven by an electric motor, is provided between the hydraulic pump 101 and the hydraulic cylinder 103 .
  • the hydraulic pump 101 is always rotatingly driven in a fixed direction and the turning direction of the outboard motor is controlled by control of the electric motor to drive the directional control valve.
  • steering member steering handle 6
  • notifying unit display 9 , main ECU 10 , step S 35 of FIG. 7C
  • main ECU 10 main ECU 10 , outboard motor ECU 30 , step S 36 of FIG. 7C
  • main ECU 10 outboard motor ECU 30 , step S 36 of FIG. 7C
  • turning angle control stopping unit main ECU 10 , turning ECU 20 , step S 28 of FIG. 7B

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • Ocean & Marine Engineering (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Combined Controls Of Internal Combustion Engines (AREA)
  • Control Of Vehicle Engines Or Engines For Specific Uses (AREA)
US14/048,262 2012-10-16 2013-10-08 Method of operating a marine vessel propulsion system, marine vessel propulsion system, and marine vessel including the same Active 2033-11-14 US8968040B2 (en)

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JP2012-228656 2012-10-16
JP2012228656A JP2014080082A (ja) 2012-10-16 2012-10-16 船舶用推進システムの運転方法、船舶用推進システムおよびそれを備えた船舶

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EP2722271B1 (en) 2018-09-26
EP2722271A2 (en) 2014-04-23
US20140106631A1 (en) 2014-04-17
EP2722271A3 (en) 2018-02-14

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